Extended demodulation reference signal scrambling identifier for demodulation reference signal communication

ABSTRACT

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a base station (BS), information identifying a quantity of demodulation reference signal (DMRS) sequences supported per antenna panel of the BS. The UE may transmit a DMRS communication having one or more DMRS sequences configured based at least in part on the quantity of DMRS sequences supported per antenna panel and scrambled using an extended DMRS scrambling identifier that is based at least in part on a physical random access channel preamble. Numerous other aspects are provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Patent Application is a continuation of U.S. patent applicationSer. No. 16/949,716, filed on Nov. 11, 2020, entitled “EXTENDEDDEMODULATION REFERENCE SIGNAL SCRAMBLING IDENTIFIER FOR DEMODULATIONREFERENCE SIGNAL COMMUNICATION,” which claims priority to U.S.Provisional Patent Application No. 62/936,243, filed on Nov. 15, 2019,entitled “EXTENDED DEMODULATION REFERENCE SIGNAL SCRAMBLING IDENTIFIERFOR DEMODULATION REFERENCE SIGNAL COMMUNICATION,” and assigned to theassignee hereof. The disclosures of the prior Applications areconsidered part of and are incorporated by reference into this PatentApplication.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wirelesscommunication and to techniques and apparatuses for extendeddemodulation reference signal (DMRS) scrambling identifier for DMRScommunication in uplink grant free transmission.

BACKGROUND

Wireless communication systems are widely deployed to provide varioustelecommunication services such as telephony, video, data, messaging,and broadcasts. Typical wireless communication systems may employmultiple-access technologies capable of supporting communication withmultiple users by sharing available system resources (e.g., bandwidth,transmit power, and/or the like). Examples of such multiple-accesstechnologies include code division multiple access (CDMA) systems, timedivision multiple access (TDMA) systems, frequency-division multipleaccess (FDMA) systems, orthogonal frequency-division multiple access(OFDMA) systems, single-carrier frequency-division multiple access(SC-FDMA) systems, time division synchronous code division multipleaccess (TD-SCDMA) systems, and Long Term Evolution (LTE).LTE/LTE-Advanced is a set of enhancements to the Universal MobileTelecommunications System (UMTS) mobile standard promulgated by theThird Generation Partnership Project (3GPP).

A wireless communication network may include a number of base stations(BSs) that can support communication for a number of user equipment(UEs). A user equipment (UE) may communicate with a base station (BS)via the downlink and uplink. The downlink (or forward link) refers tothe communication link from the BS to the UE, and the uplink (or reverselink) refers to the communication link from the UE to the BS. As will bedescribed in more detail herein, a BS may be referred to as a Node B, agNB, an access point (AP), a radio head, a transmit receive point (TRP),a New Radio (NR) BS, a 5G Node B, and/or the like.

The above multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent user equipment to communicate on a municipal, national,regional, and even global level. New Radio (NR), which may also bereferred to as 5G, is a set of enhancements to the LTE mobile standardpromulgated by the Third Generation Partnership Project (3GPP). NR isdesigned to better support mobile broadband Internet access by improvingspectral efficiency, lowering costs, improving services, making use ofnew spectrum, and better integrating with other open standards usingorthogonal frequency division multiplexing (OFDM) with a cyclic prefix(CP) (CP-OFDM) on the downlink (DL), using CP-OFDM and/or SC-FDM (e.g.,also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) onthe uplink (UL), as well as supporting beamforming, multiple-inputmultiple-output (MIMO) antenna technology, and carrier aggregation.However, as the demand for mobile broadband access continues toincrease, there exists a need for further improvements in LTE and NRtechnologies. Preferably, these improvements should be applicable toother multiple access technologies and the telecommunication standardsthat employ these technologies.

SUMMARY

In some aspects, a method of wireless communication performed by a userequipment (UE) includes receiving, from a base station (BS), informationidentifying a quantity of demodulation reference signal (DMRS) sequencessupported per antenna panel of the BS; and transmitting a DMRScommunication having one or more DMRS sequences configured based atleast in part on the quantity of DMRS sequences supported per antennapanel and scrambled using an extended DMRS scrambling identifier that isbased at least in part on a physical random access channel preamble.

In some aspects, a UE for wireless communication includes a memory andone or more processors coupled with the memory, the memory and the oneor more processors configured to receive, from a BS, informationidentifying a quantity of DMRS sequences supported per antenna panel ofthe BS; and transmit a DMRS communication having one or more DMRSsequences configured based at least in part on the quantity of DMRSsequences supported per antenna panel and scrambled using an extendedDMRS scrambling identifier that is based at least in part on a physicalrandom access channel preamble.

In some aspects, a non-transitory computer-readable medium storing oneor more instructions for wireless communication includes one or moreinstructions that, when executed by one or more processors of a UE,cause the one or more processors to receive, from a BS, informationidentifying a quantity of DMRS sequences supported per antenna panel ofthe BS; and transmit a DMRS communication having one or more DMRSsequences configured based at least in part on the quantity of DMRSsequences supported per antenna panel and scrambled using an extendedDMRS scrambling identifier that is based at least in part on a physicalrandom access channel preamble

In some aspects, an apparatus for wireless communication includes meansfor receiving, from a BS, information identifying a quantity of DMRSsequences supported per antenna panel of the BS; and means fortransmitting a DMRS communication having one or more DMRS sequencesconfigured based at least in part on the quantity of DMRS sequencessupported per antenna panel and scrambled using an extended DMRSscrambling identifier that is based at least in part on a physicalrandom access channel preamble.

Aspects generally include a method, apparatus, system, computer programproduct, non-transitory computer-readable medium, user equipment, basestation, wireless communication device, and/or processing system assubstantially described herein with reference to and as illustrated bythe accompanying drawings and specification.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purposesof illustration and description, and not as a definition of the limitsof the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the above-recited features of the present disclosure can beunderstood in detail, a more particular description, briefly summarizedabove, may be had by reference to aspects, some of which are illustratedin the appended drawings. It is to be noted, however, that the appendeddrawings illustrate only certain typical aspects of this disclosure andare therefore not to be considered limiting of its scope, for thedescription may admit to other equally effective aspects. The samereference numbers in different drawings may identify the same or similarelements.

FIG. 1 is a block diagram conceptually illustrating an example of awireless communication network, in accordance with various aspects ofthe present disclosure.

FIG. 2 is a block diagram conceptually illustrating an example of a basestation in communication with a UE in a wireless communication network,in accordance with various aspects of the present disclosure.

FIG. 3 is a diagram illustrating an example of a channel structure fortransmitting a physical random access channel (PRACH) message type A(msgA), in accordance with various aspects of the present disclosure.

FIG. 4 is a diagram illustrating an example of a resource mapping fortransmitting a PRACH msgA, in accordance with various aspects of thepresent disclosure.

FIG. 5 is a diagram illustrating an example of a transmit chain fortransmitting a PRACH msgA, in accordance with various aspects of thepresent disclosure.

FIG. 6 is a diagram illustrating an example of using an extended DMRSscrambling identifier for DMRS communication, in accordance with variousaspects of the present disclosure.

FIG. 7 is a diagram illustrating an example process performed, forexample, by a user equipment, in accordance with various aspects of thepresent disclosure.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully hereinafterwith reference to the accompanying drawings. This disclosure may,however, be embodied in many different forms and should not be construedas limited to any specific structure or function presented throughoutthis disclosure. Rather, these aspects are provided so that thisdisclosure will be thorough and complete, and will fully convey thescope of the disclosure to those skilled in the art. Based on theteachings herein one skilled in the art should appreciate that the scopeof the disclosure is intended to cover any aspect of the disclosuredisclosed herein, whether implemented independently of or combined withany other aspect of the disclosure. For example, an apparatus may beimplemented or a method may be practiced using any number of the aspectsset forth herein. In addition, the scope of the disclosure is intendedto cover such an apparatus or method which is practiced using otherstructure, functionality, or structure and functionality in addition toor other than the various aspects of the disclosure set forth herein. Itshould be understood that any aspect of the disclosure disclosed hereinmay be embodied by one or more elements of a claim.

Several aspects of telecommunication systems will now be presented withreference to various apparatuses and techniques. These apparatuses andtechniques will be described in the following detailed description andillustrated in the accompanying drawings by various blocks, modules,components, circuits, steps, processes, algorithms, and/or the like(collectively referred to as “elements”). These elements may beimplemented using hardware, software, or combinations thereof. Whethersuch elements are implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem.

It should be noted that while aspects may be described herein usingterminology commonly associated with 3G and/or 4G wireless technologies,aspects of the present disclosure can be applied in othergeneration-based communication systems, such as 5G and later, includingNR technologies.

FIG. 1 is a diagram illustrating a wireless network 100 in which aspectsof the present disclosure may be practiced. The wireless network 100 maybe an LTE network or some other wireless network, such as a 5G or NRnetwork. The wireless network 100 may include a number of BSs 110 (shownas BS 110 a, BS 110 b, BS 110 c, and BS 110 d) and other networkentities. A BS is an entity that communicates with user equipment (UEs)and may also be referred to as a base station, a NR BS, a Node B, a gNB,a 5G node B (NB), an access point, a transmit receive point (TRP),and/or the like. Each BS may provide communication coverage for aparticular geographic area. In 3GPP, the term “cell” can refer to acoverage area of a BS and/or a BS subsystem serving this coverage area,depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, afemto cell, and/or another type of cell. A macro cell may cover arelatively large geographic area (e.g., several kilometers in radius)and may allow unrestricted access by UEs with service subscription. Apico cell may cover a relatively small geographic area and may allowunrestricted access by UEs with service subscription. A femto cell maycover a relatively small geographic area (e.g., a home) and may allowrestricted access by UEs having association with the femto cell (e.g.,UEs in a closed subscriber group (CSG)). A BS for a macro cell may bereferred to as a macro BS. A BS for a pico cell may be referred to as apico BS. A BS for a femto cell may be referred to as a femto BS or ahome BS. In the example shown in FIG. 1 , a BS 110 a may be a macro BSfor a macro cell 102 a, a BS 110 b may be a pico BS for a pico cell 102b, and a BS 110 c may be a femto BS for a femto cell 102 c. A BS maysupport one or multiple (e.g., three) cells. The terms “eNB”, “basestation”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” maybe used interchangeably herein.

In some aspects, a cell may not necessarily be stationary, and thegeographic area of the cell may move according to the location of amobile BS. In some aspects, the BSs may be interconnected to one anotherand/or to one or more other BSs or network nodes (not shown) in thewireless network 100 through various types of backhaul interfaces suchas a direct physical connection, a virtual network, and/or the likeusing any suitable transport network.

Wireless network 100 may also include relay stations. A relay station isan entity that can receive a transmission of data from an upstreamstation (e.g., a BS or a UE) and send a transmission of the data to adownstream station (e.g., a UE or a BS). A relay station may also be aUE that can relay transmissions for other UEs. In the example shown inFIG. 1 , a relay station 110 d may communicate with macro BS 110 a and aUE 120 d in order to facilitate communication between BS 110 a and UE120 d. A relay station may also be referred to as a relay BS, a relaybase station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs ofdifferent types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/orthe like. These different types of BSs may have different transmit powerlevels, different coverage areas, and different impacts on interferencein wireless network 100. For example, macro BSs may have a high transmitpower level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relayBSs may have lower transmit power levels (e.g., 0.1 to 2 watts).

A network controller 130 may couple to a set of BSs and may providecoordination and control for these BSs. Network controller 130 maycommunicate with the BSs via a backhaul. The BSs may also communicatewith one another (directly or indirectly) via a wireless or wirelinebackhaul.

UEs 120 (e.g., 120 a, 120 b, 120 c) may be dispersed throughout wirelessnetwork 100, and each UE may be stationary or mobile. A UE may also bereferred to as an access terminal, a terminal, a mobile station, asubscriber unit, a station, and/or the like. A UE may be a cellularphone (e.g., a smart phone), a personal digital assistant (PDA), awireless modem, a wireless communication device, a handheld device, alaptop computer, a cordless phone, a wireless local loop (WLL) station,a tablet, a camera, a gaming device, a netbook, a smartbook, anultrabook, a medical device or equipment, biometric sensors/devices,wearable devices (smart watches, smart clothing, smart glasses, smartwrist bands, smart jewelry (e.g., smart ring, smart bracelet)), anentertainment device (e.g., a music or video device, or a satelliteradio), a vehicular component or sensor, smart meters/sensors,industrial manufacturing equipment, a global positioning system device,or any other suitable device that is configured to communicate via awireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolvedor enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEsinclude, for example, robots, drones, remote devices, sensors, meters,monitors, location tags, and/or the like, that may communicate with abase station, another device (e.g., remote device), or some otherentity. A wireless node may provide, for example, connectivity for or toa network (e.g., a wide area network such as Internet or a cellularnetwork) via a wired or wireless communication link. Some UEs may beconsidered Internet-of-Things (IoT) devices, and/or may be implementedas NB-IoT (narrowband internet of things) devices. Some UEs may beconsidered a Customer Premises Equipment (CPE). UE 120 may be includedinside a housing that houses components of UE 120, such as processorcomponents, memory components, and/or the like.

In general, any number of wireless networks may be deployed in a givengeographic area. Each wireless network may support a particular radioaccess technology (RAT) and may operate on one or more frequencies. ARAT may also be referred to as a radio technology, an air interface,and/or the like. A frequency may also be referred to as a carrier, afrequency channel, and/or the like. Each frequency may support a singleRAT in a given geographic area in order to avoid interference betweenwireless networks of different RATs. In some cases, NR or 5G RATnetworks may be deployed.

In some aspects, two or more UEs 120 (e.g., shown as UE 120 a and UE 120e) may communicate directly using one or more sidelink channels (e.g.,without using a base station 110 as an intermediary to communicate withone another). For example, the UEs 120 may communicate usingpeer-to-peer (P2P) communications, device-to-device (D2D)communications, a vehicle-to-everything (V2X) protocol (e.g., which mayinclude a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure(V2I) protocol, vehicle-to-pedestrian (V2P) protocol, and/or the like),a mesh network, and/or the like. In this case, the UE 120 may performscheduling operations, resource selection operations, and/or otheroperations described elsewhere herein as being performed by the basestation 110.

As indicated above, FIG. 1 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 1 .

FIG. 2 shows a block diagram of a design 200 of base station 110 and UE120, which may be one of the base stations and one of the UEs in FIG. 1. Base station 110 may be equipped with T antennas 234 a through 234 t,and UE 120 may be equipped with R antennas 252 a through 252 r, where ingeneral T≥1 and R≥1.

At base station 110, a transmit processor 220 may receive data from adata source 212 for one or more UEs, select one or more modulation andcoding schemes (MCS) for each UE based at least in part on channelquality indicators (CQIs) received from the UE, process (e.g., encodeand modulate) the data for each UE based at least in part on the MCS(s)selected for the UE, and provide data symbols for all UEs. Transmitprocessor 220 may also process system information (e.g., for semi-staticresource partitioning information (SRPI) and/or the like) and controlinformation (e.g., CQI requests, grants, upper layer signaling, and/orthe like) and provide overhead symbols and control symbols. Transmitprocessor 220 may also generate reference symbols for reference signals(e.g., the cell-specific reference signal (CRS)) and synchronizationsignals (e.g., the primary synchronization signal (PSS) and secondarysynchronization signal (SSS)). A transmit (TX) multiple-inputmultiple-output (MIMO) processor 230 may perform spatial processing(e.g., precoding) on the data symbols, the control symbols, the overheadsymbols, and/or the reference symbols, if applicable, and may provide Toutput symbol streams to T modulators (MODs) 232 a through 232 t. Eachmodulator 232 may process a respective output symbol stream (e.g., forOFDM and/or the like) to obtain an output sample stream. Each modulator232 may further process (e.g., convert to analog, amplify, filter, andupconvert) the output sample stream to obtain a downlink signal. Tdownlink signals from modulators 232 a through 232 t may be transmittedvia T antennas 234 a through 234 t, respectively. According to variousaspects described in more detail below, the synchronization signals canbe generated with location encoding to convey additional information.

At UE 120, antennas 252 a through 252 r may receive the downlink signalsfrom base station 110 and/or other base stations and may providereceived signals to demodulators (DEMODs) 254 a through 254 r,respectively. Each demodulator 254 may condition (e.g., filter, amplify,downconvert, and digitize) a received signal to obtain input samples.Each demodulator 254 may further process the input samples (e.g., forOFDM and/or the like) to obtain received symbols. A MIMO detector 256may obtain received symbols from all R demodulators 254 a through 254 r,perform MIMO detection on the received symbols if applicable, andprovide detected symbols. A receive processor 258 may process (e.g.,demodulate and decode) the detected symbols, provide decoded data for UE120 to a data sink 260, and provide decoded control information andsystem information to a controller/processor 280. A channel processormay determine reference signal received power (RSRP), received signalstrength indicator (RSSI), reference signal received quality (RSRQ),channel quality indicator (CQI), and/or the like. In some aspects, oneor more components of UE 120 may be included in a housing.

On the uplink, at UE 120, a transmit processor 264 may receive andprocess data from a data source 262 and control information (e.g., forreports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) fromcontroller/processor 280. Transmit processor 264 may also generatereference symbols for one or more reference signals. The symbols fromtransmit processor 264 may be precoded by a TX MIMO processor 266 ifapplicable, further processed by modulators 254 a through 254 r (e.g.,for DFT-s-OFDM, CP-OFDM, and/or the like), and transmitted to basestation 110. At base station 110, the uplink signals from UE 120 andother UEs may be received by antennas 234, processed by demodulators232, detected by a MIMO detector 236 if applicable, and furtherprocessed by a receive processor 238 to obtain decoded data and controlinformation sent by UE 120. Receive processor 238 may provide thedecoded data to a data sink 239 and the decoded control information tocontroller/processor 240. Base station 110 may include communicationunit 244 and communicate to network controller 130 via communicationunit 244. Network controller 130 may include communication unit 294,controller/processor 290, and memory 292.

Controller/processor 240 of base station 110, controller/processor 280of UE 120, and/or any other component(s) of FIG. 2 may perform one ormore techniques associated with using an extended demodulation referencesignal (DMRS) scrambling identifier for DMRS communication, as describedin more detail elsewhere herein. For example, controller/processor 240of base station 110, controller/processor 280 of UE 120, and/or anyother component(s) of FIG. 2 may perform or direct operations of, forexample, process 700 of FIG. 7 and/or other processes as describedherein. Memories 242 and 282 may store data and program codes for basestation 110 and UE 120, respectively. In some aspects, memory 242 and/ormemory 282 may comprise a non-transitory computer-readable mediumstoring one or more instructions for wireless communication. Forexample, the one or more instructions, when executed by one or moreprocessors of the base station 110 and/or the UE 120, may perform ordirect operations of, for example, process 700 of FIG. 7 and/or otherprocesses as described herein. A scheduler 246 may schedule UEs for datatransmission on the downlink and/or uplink.

In some aspects, UE 120 may include means for receiving, from a basestation (e.g., BS 110), information identifying a quantity of DMRSsequences supported per antenna panel of the BS or means fortransmitting a DMRS communication having one or more DMRS sequencesconfigured based at least in part on the quantity of DMRS sequencessupported per antenna panel and scrambled using an extended DMRSscrambling identifier that is based at least in part on a physicalrandom access channel preamble, among other examples. In some aspects,such means may include one or more components of UE 120 described inconnection with FIG. 2 , such as controller/processor 280, transmitprocessor 264, TX MIMO processor 266, MOD 254, antenna 252, DEMOD 254,MIMO detector 256, receive processor 258, and/or the like.

As indicated above, FIG. 2 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 2 .

FIG. 3 is a diagram illustrating an example 300 of a channel structurefor transmitting a physical random access channel (PRACH) message type A(msgA), in accordance with various aspects of the present disclosure.

As shown in FIG. 3 , a channel structure for transmitting a PRACH msgAmay include resources allocated for a preamble section (msgA Preamble)and a payload section (msgA payload). The preamble section, which mayinclude a cyclic prefix (CP), is in time and frequency resourcesallocated for PRACH transmission (T_(PRACH)). After the time resourcesallocated for the PRACH transmission, the channel structure may includetime and frequency resources allocated as a guard period and/or a gapperiod (T_(G,1) and T_(gap,2), respectively) to enable transitioning ofa transmit chain from msgA preamble transmission to msgA payloadtransmission. As shown, the msgA payload section may include a DMRStransmission that is multiplexed with a physical uplink shared channel(PUSCH) transmission, as described in more detail herein. The msgApayload section may include a guard period (T_(G,2)) to enable a UE totransition from transmitting the PRACH msgA to transmitting anothercommunication or receiving a communication.

As indicated above, FIG. 3 is provided as an example. Other examples maydiffer from what is described with respect to FIG. 3 .

FIG. 4 is a diagram illustrating an example 400 of a resource mappingfor transmitting a PRACH msgA, in accordance with various aspects of thepresent disclosure.

As shown in FIG. 4 , a msgA transmission occasion may include timeresources and frequency resources that map to a synchronization signalblock (SSB) of a set of SSBs. The msgA transmission occasion may occurin an initial or an active uplink bandwidth part (BWP) and may include arandom access channel (RACH) slot with a set of RACH occasions (ROs).Further, the msgA transmission occasion may include one or moredifferent types of PUSCH configurations, such as an msgA PUSCHconfiguration #1 and an msgA PUSCH configuration #2.

In some aspects, a BS may configure, when a UE is in a radio resourcecontrol (RRC) idle state or an RRC inactive state, a first set of twodifferent transport block sizes (TBSs) for the msgA PUSCH in a systeminformation. The first set of two different TBSs may be configured fortransmission in an initial BWP. In contrast, the BS may configure, whenthe UE is in an RRC connected state, a second set of two different TBSsfor the msgA PUSCH. In this case, the BS may configure the second set ofTBSs in RRC signaling for an active bandwidth part (e.g., which may bethe same or different from the initial bandwidth part). Based at leastin part on receiving information identifying a set of transport blocksizes from the BS, the UE may select a particular TBS based at least inpart on a layer 1 reference signal received power (RSRP) measurement, acontent of a msgA data buffer, a satisfaction of a msgA group sizeparameter, and/or the like.

As indicated above, FIG. 4 is provided as an example. Other examples maydiffer from what is described with respect to FIG. 4 .

FIG. 5 is a diagram illustrating an example 500 of a transmit chain fortransmitting a PRACH msgA, in accordance with various aspects of thepresent disclosure.

As shown in FIG. 5 , a UE, such as UE 120, may include a transmit chainfor transmitting msgA. In this case, the UE may receive, at the transmitchain, a payload and cyclic redundancy check (CRC) and may performchannel coding and rate matching on the payload and CRC to generate bitsfor transmission. After performing channel coding and rate matching, theUE may use a scrambling sequence to scramble bits of the payload andCRC. For example, the bit scrambling module may use a scramblingsequence of the form:

C _(init)=RA-RNTI×2¹⁶+RAPID×2¹⁰ +n _(ID),

where C_(init) represents an initial value of the scrambling sequence,RA-RNTI is a random access (RA) radio network temporary identifier(RNTI), and n_(ID) represents an initialization value based at least inpart on a UE identifier.

As further shown in FIG. 5 , based on scrambling bits, the UE mayperform linear modulation and, in some cases, transform precoding, asdescribed in more detail herein. After linear modulation (and transformprecoding, in some cases), the UE may perform inversefast-Fourier-transform (IFFT) processing. After IFFT processing, the UEmay multiplex a DMRS with the payload and CRC (e.g., symbols generatedbased at least in part on bits thereof). After multiplexing the DMRSwith the payload and the CRC, the UE may perform radio resource mappingto generate a msgA preamble based at least in part on a PRACH preambleand a msgA payload based at least in part on the payload and CRC and theDMRS.

A UE may generate the DMRS for multiplexing with content of msgA using aDMRS scrambling identifier. The UE may determine the DMRS scramblingidentifier based at least in part on a waveform of a correspondingphysical uplink shared channel (PUSCH) of the msgA. In contention basedrandom access (CBRA)-based two-step random access channel (RACH)procedures, using a DMRS scrambling identifier based at least in part ona PUSCH waveform (e.g., a discrete Fourier transform spread orthogonalfrequency division multiplexing (DFT-s-OFDM) waveform or a cyclic prefixorthogonal frequency division multiplexing (CP-OFDM) waveform) mayresult in a collision between different DMRSs. This may result indropped communications, reduced throughput, and/or the like.

Thus, some aspects described herein enable the UE to use an extendedDMRS scrambling identifier, for a DMRS, that is determined based atleast in part on a scrambling identifier for a msgA PUSCH that is to bemultiplexed with the DMRS. For example, the UE may determine theextended DMRS scrambling identifier based at least in part on the PRACHpreamble, as shown. In this way, by reusing the PRACH preamble fordetermining the extended DMRS scrambling identifier, the UE reduces alikelihood of collision with increasing a processing and/or memoryutilization associated with using other types of dedicated DMRSscrambling identifier for various waveforms.

In some aspects, the UE may determine the extended DMRS scramblingidentifier based at least in part on the quantity of DMRS sequences thatare supported per antenna panel of the BS. In some aspects, the UE maymap the PRACH preamble to a PUSCH resource unit (PRU) to determine theextended DMRS scrambling identifier and perform a DMRS generationprocedure. In this way, the UE may generate an extended DMRS scramblingidentifier that reduces a likelihood of collision during CBRA-basedtwo-step RACH.

As indicated above, FIG. 5 is provided as an example. Other examples maydiffer from what is described with respect to FIG. 5 .

FIG. 6 is a diagram illustrating an example 600 of using an extendedDMRS scrambling identifier for DMRS communication, in accordance withvarious aspects of the present disclosure. As shown in FIG. 6 , example600 includes a BS 110 in communication with a UE 120.

As further shown in FIG. 6 , and by reference number 610, UE 120 mayreceive information identifying the quantity of DMRS sequences supportedper antenna panel of BS 110. For example, BS 110 may transmitinformation identifying the quantity of DMRS sequences supported perantenna panel to a group of UEs 120 that includes the UE. In someaspects, UE 120 may receive DMRS sequence configuration information fromBS 110 based at least in part on BS 110 configuring one or more DMRSsequences for a DMRS communication (e.g., by using a‘msgA-ScramblingID0’ parameter or a ‘msgA-ScramblingID1’ parameter, orby configuring one or more additional DMRS positions, among otherexamples). In this case, BS 110 may configure the one or more DMRSsequences based at least in part on a quantity of DMRS sequencessupported per antenna panel. In some aspects, UE 120 may receiveinformation indicating that BS 110 supports 4 DMRS sequences per antennapanel, 8 DMRS sequences per antenna panel, and/or the like. In thiscase, a quantity of DMRS sequences may correspond to a quantity of DMRSscrambling identifiers (e.g., extended DMRS scrambling identifiers)supported per antenna panel. In some aspects, BS 110 may configure theextended DMRS scrambling identifiers on a per antenna port basis andprovide system information or RRC signaling to UE 120 to identify theconfigured extended DMRS scrambling identifiers.

As further shown in FIG. 6 , and by reference number 620, UE 120 mayconfigure one or more DMRS sequences for a DMRS communication. Forexample, UE 120 may configure the one or more DMRS sequences based atleast in part on the quantity of DMRS sequences supported per antennapanel. Additionally, or alternatively, UE 120 may configure the one ormore DMRS sequences based at least in part on a PRACH preamble. Forexample, UE 120 may scramble the one or more DMRS sequences using anextended DMRS scrambling identifier that is based at least in part onthe PRACH preamble. In this way, UE 120 may reuse a scramblingidentifier of a msgA PUSCH that is to be transmitted together with theDMRS communication, as described above. In some aspects, UE 120 may mapthe PRACH preamble to a PRU to reuse the scrambling identifier of themsgA PUSCH for the extended DMRS scrambling identifier.

In this case, UE 120 may support one or more different possible mappingratios. For example, UE 120 may determine the mapping ratio based atleast in part on a quantity of PRACH sequences assigned for a msgApreamble on valid RACH occasions (ROs) and a quantity of PRUs assignedfor msgA payload on valid PUSCH occasions (POs). In some aspects, UE 120may determine the mapping ratio based at least in part on a receivedbroadcast from BS 110 (e.g., of a system information) or via RRCsignaling from BS 110. Additionally, or alternatively, after validationof a msgA resource occasion and msgA RO and a msgA PO for a two-stepRACH, UE 120 may determine the mapping ratio based at least in part on avalidation rule and a mapping order (e.g., received from BS 110). Insome aspects, each msgA PUSCH configuration in an initial or activebandwidth part may be associated with a single mapping ratio, anddifferent msgA PUSCH configurations may have different mapping ratios.The mapping ratio may be valid for at least a mapping period betweenmsgA ROs and msgA PUSCH POs. In this case, the mapping period may be acommon multiple of an SSB to RO association pattern period for each msgAPUSCH configuration.

In some aspects, UE 120 may generate the DMRS communication using aparticular DMRS pattern. For example, UE 120 may generate a type-I DMRSpattern-based DMRS, a type-II DMRS pattern-based DMRS, and/or the like.

In some aspects, UE 120 may determine the extended DMRS scramblingidentifier based at least in part on a type of waveform for atransmission that includes the msgA PUSCH and the DMRS communication.For example, for a CP-OFDM waveform and when transform precoding is notenabled, UE 120 may determine the extended DMRS scrambling identifierbased at least in part on an equation of the form:

$c_{{init},{msgA\_ DMRS}}\overset{\Delta}{=}{c_{{init},{msgA}_{PUSCH}} = {{{RA} - {RNTI}*2^{16}} + {{RAPID}*2^{10}} + {n_{ID}.}}}$

In this case, UE 120 reuses the bit scrambling sequence applied to thepayload and CRC of the msgA, as described above. Additionally, oralternatively, UE 120 may determine the extended DMRS scramblingidentifier based at least in part on an equation of the form:

c_(init,msgA_DRMS)(2¹⁷(N_(symb) ^(slot)n_(s,f) ^(μ)+l+1)*

c_(init,msgA) _(PUSCH)

_(K1)+

c_(init,msgA) _(PUSCH)

_(K2))mod 2³¹,

where l is the OFDM symbol number within a slot, n_(s,f) ^(μ) is theslot number within a frame, and

⋅

is an inner quantity operator (e.g., truncating an inner quantity to Kmost significant bits (MSBs) or least significant bits (LSBs)). In thiscase, UE 120 determines the extended DMRS scrambling identifier based atleast in part on the bit scrambling sequence, a symbol number for theDMRS, a slot number for the DMRS, and/or the like.

Additionally, or alternatively, when the waveform is a DFT-s-OFDMwaveform and transform precoding is enabled, UE 120 may determine anextended DMRS scrambling identifier for group hopping and sequencehopping, such that:

u=(f _(gh) +n _(ID) ^(RS))mod 30

v=0

f _(gh)=(Σ_(m=0) ⁷2^(m) c(8(N _(symb) ^(s) n _(s,f) ^(μ) +l)+m))mod 30

In this case, UE 120 may determine n_(ID) ^(RS) as:

$n_{ID}^{RS}\overset{\Delta}{=}c_{{init},{msgA\_ PUSCH}}$

Additionally, or alternatively, UE 120 may determine n_(ID) ^(RS) as:

$n_{ID}^{RS}\overset{\Delta}{=}{\left\langle c_{{init},{msgA\_ PUSCH}} \right\rangle_{K1} \times \left\langle c_{{init},{msgA\_ PUSCH}} \right\rangle_{K2}}$

In this case, support for CP-OFDM or DFT-s-OFDM waveforms, as describedabove, may correspond to UE 120 determining whether to apply transformprecoding for PUSCH transmission (e.g., using CP-OFDM may correspond tonot using transform precoding, and using DFT-s-OFDM may correspond tousing transform precoding).

As further shown in FIG. 6 , and by reference number 630, UE 120 maytransmit the DMRS communication. For example, based at least in part onconfiguring the DMRS sequences using the extended DMRS scramblingidentifier, UE 120 may transmit a DMRS multiplexed with a msgA PUSCH. Inthis way, BS 110 and UE 120 reduce a likelihood collision between DMRSsin CBRA-based two-step RACH.

As indicated above, FIG. 6 is provided as an example. Other examples maydiffer from what is described with respect to FIG. 6 .

FIG. 7 is a diagram illustrating an example process 700 performed, forexample, by a UE, in accordance with various aspects of the presentdisclosure. Example process 700 is an example where the UE (e.g., UE 120and/or the like) performs operations associated with using an extendeddemodulation reference signal scrambling identifier for demodulationreference signal communication.

As shown in FIG. 7 , in some aspects, process 700 may include receiving,from a BS, information identifying a quantity of DMRS sequencessupported per antenna panel of the BS (block 710). For example, the UE(e.g., using antenna 252, DEMOD 254, MIMO detector 256, receiveprocessor 258, or controller/processor 280, among other examples) mayreceive, from a BS, information identifying a quantity of DMRS sequencessupported per antenna panel of the BS, as described above.

As further shown in FIG. 7 , in some aspects, process 700 may includetransmitting a DMRS communication, with one or more DMRS sequencesconfigured based at least in part on the quantity of DMRS sequencessupported per antenna panel and scrambled using an extended DMRSscrambling identifier that is based at least in part on a physicalrandom access channel preamble (block 720). For example, the UE (e.g.,using controller/processor 280, transmit processor 264, TX MIMOprocessor 266, MOD 254, or antenna 252, among other examples) maytransmit a DMRS communication, with one or more DMRS sequencesconfigured based at least in part on the quantity of DMRS sequencessupported per antenna panel and scrambled using an extended DMRSscrambling identifier that is based at least in part on a physicalrandom access channel preamble, as described above.

Process 700 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, process 700 includes configuring the one or more DMRSsequences, which includes generating a waveform for the DMRScommunication, where the waveform for the DMRS communication is acyclic-prefix orthogonal frequency division multiplexing (CP-OFDM)waveform or a discrete Fourier transform spread orthogonal frequencydivision multiplexing (DFT-s-OFDM) waveform.

In a second aspect, alone or in combination with the first aspect, thequantity of DMRS sequences supported per antenna panel is 4 or 8.

In a third aspect, alone or in combination with one or more of the firstand second aspects, a DMRS pattern of the one or more DMRS sequences isa Type-I DMRS pattern or a Type-II DMRS pattern.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, configuring the one or more DMRS sequencesincludes mapping the physical random access channel preamble to aphysical uplink shared channel resource unit including the one or moreDMRS sequences in connection with a mapping ratio within a mappingperiod between preamble and PUSCH resource unit.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, the DMRS communication is associated with aphysical uplink shared channel with transform precoding.

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, the DMRS communication is associated with aphysical uplink shared channel without transform precoding.

In a seventh aspect, alone or in combination with one or more of thefirst through sixth aspects, the extended DMRS scrambling identifier isbased at least in part on a physical uplink shared channel scramblingidentifier of a physical random access channel message associated withthe physical random access channel preamble.

In an eighth aspect, alone or in combination with one or more of thefirst through seventh aspects, the extended DMRS scrambling identifieris configured on a per antenna port basis via a system information orradio resource control transmission.

In a ninth aspect, alone or in combination with one or more of the firstthrough eighth aspects, process 700 may include determining the mappingratio based at least in part on at least one of a received systeminformation transmission from the BS, a received radio resource controltransmission from the BS, a set of validation rules, or a mapping order.

In a tenth aspect, alone or in combination with one or more of the firstthrough ninth aspects, the mapping ratio is defined for a PUSCHconfiguration, such that each PUSCH configuration, of a plurality ofPUSCH configurations, in an initial or active bandwidth part isassociated with a single mapping ratio.

In an eleventh aspect, alone or in combination with one or more of thefirst through tenth aspects, a first PUSCH configuration of theplurality of PUSCH configurations is associated with a different mappingratio than a second PUSCH configuration of the plurality of PUSCHconfigurations.

In a twelfth aspect, alone or in combination with one or more of thefirst through eleventh aspects, the mapping period is based at least inpart on a synchronization signal block to resource occasion associationpattern period.

In a thirteenth aspect, alone or in combination with one or more of thefirst through twelfth aspects, process 700 may include configuring theone or more DMRS sequences for the DMRS communication based at least inpart on the quantity of DMRS sequences supported per antenna panel andthe physical random access channel preamble; and transmitting the DMRScommunication may include transmitting the DMRS communication based atleast in part on configuring the one or more DMRS sequences for the DMRScommunication.

Although FIG. 7 shows example blocks of process 700, in some aspects,process 700 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 7 .Additionally, or alternatively, two or more of the blocks of process 700may be performed in parallel.

The foregoing disclosure provides illustration and description, but isnot intended to be exhaustive or to limit the aspects to the preciseform disclosed. Modifications and variations may be made in light of theabove disclosure or may be acquired from practice of the aspects.

As used herein, the term “component” is intended to be broadly construedas hardware, firmware, and/or a combination of hardware and software. Asused herein, a processor is implemented in hardware, firmware, and/or acombination of hardware and software.

As used herein, satisfying a threshold may, depending on the context,refer to a value being greater than the threshold, greater than or equalto the threshold, less than the threshold, less than or equal to thethreshold, equal to the threshold, not equal to the threshold, and/orthe like.

It will be apparent that systems and/or methods described herein may beimplemented in different forms of hardware, firmware, and/or acombination of hardware and software. The actual specialized controlhardware or software code used to implement these systems and/or methodsis not limiting of the aspects. Thus, the operation and behavior of thesystems and/or methods were described herein without reference tospecific software code—it being understood that software and hardwarecan be designed to implement the systems and/or methods based, at leastin part, on the description herein.

Even though particular combinations of features are recited in theclaims and/or disclosed in the specification, these combinations are notintended to limit the disclosure of various aspects. In fact, many ofthese features may be combined in ways not specifically recited in theclaims and/or disclosed in the specification. Although each dependentclaim listed below may directly depend on only one claim, the disclosureof various aspects includes each dependent claim in combination withevery other claim in the claim set. A phrase referring to “at least oneof” a list of items refers to any combination of those items, includingsingle members. As an example, “at least one of: a, b, or c” is intendedto cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combinationwith multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c,a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering ofa, b, and c).

No element, act, or instruction used herein should be construed ascritical or essential unless explicitly described as such. Also, as usedherein, the articles “a” and “an” are intended to include one or moreitems, and may be used interchangeably with “one or more.” Furthermore,as used herein, the terms “set” and “group” are intended to include oneor more items (e.g., related items, unrelated items, a combination ofrelated and unrelated items, and/or the like), and may be usedinterchangeably with “one or more.” Where only one item is intended, thephrase “only one” or similar language is used. Also, as used herein, theterms “has,” “have,” “having,” and/or the like are intended to beopen-ended terms. Further, the phrase “based on” is intended to mean“based, at least in part, on” unless explicitly stated otherwise.

What is claimed is:
 1. A user equipment (UE) for wireless communication,comprising: one or more memories; and one or more processors coupledwith the one or more memories, the one or more processors configured to:receive, from a network entity, information identifying a quantity ofdemodulation reference signal (DMRS) sequences supported per antennapanel of the network entity; and transmit a DMRS communication havingone or more DMRS sequences configured based at least in part on thequantity of DMRS sequences supported per antenna panel and scrambledusing a DMRS scrambling identifier.
 2. The UE of claim 1, wherein theDMRS scrambling identifier is based at least in part on a physicalrandom access channel preamble.
 3. The UE of claim 2, wherein the one ormore processors are further configured to: utilize a scrambling sequencebased at least in part on the physical random access channel preamble toscramble bits of a payload and cyclic redundancy check.
 4. The UE ofclaim 2, wherein the DMRS communication is associated with an uplinkshared channel of a physical random access channel message associatedwith the physical random access channel preamble.
 5. The UE of claim 1,wherein the DMRS scrambling identifier is based at least in part on aphysical uplink shared channel (PUSCH) scrambling identifier.
 6. The UEof claim 1, wherein the DMRS scrambling identifier is based at least inpart on a radio network temporary identifier.
 7. The UE of claim 1,wherein the one or more processors, to transmit the DMRS communication,are configured to: transmit the DMRS communication based at least inpart on configuring the one or more DMRS sequences for the DMRScommunication.
 8. The UE of claim 7, wherein the one or more processors,to configure the one or more DMRS sequences, are configured to: generatea waveform for the DMRS communication, wherein the waveform for the DMRScommunication is a cyclic-prefix orthogonal frequency divisionmultiplexing (CP-OFDM) waveform or a discrete Fourier transform spreadorthogonal frequency division multiplexing (DFT-s-OFDM) waveform.
 9. TheUE of claim 1, wherein the quantity of DMRS sequences supported perantenna panel is 4 or
 8. 10. The UE of claim 1, wherein a DMRS patternof the one or more DMRS sequences is a Type-I DMRS pattern or a Type-IIDMRS pattern.
 11. The UE of claim 1, wherein the DMRS scramblingidentifier is configured on a per antenna port basis via a systeminformation or radio resource control transmission.
 12. The UE of claim1, wherein the one or more processors are further configured to: map arandom access channel preamble to a physical uplink shared channel(PUSCH) resource unit including the one or more DMRS sequences inconnection with a mapping ratio within a mapping period between therandom access channel preamble and the PUSCH resource unit.
 13. The UEof claim 12, wherein the one or more processors are further configuredto: determine the mapping ratio based at least in part on at least oneof: a received system information transmission from the network entity,a received radio resource control transmission from the network entity,a set of validation rules, or a mapping order.
 14. The UE of claim 12,wherein the mapping ratio is defined for a physical uplink sharedchannel (PUSCH) configuration, such that each PUSCH configuration, of aplurality of PUSCH configurations, in an initial or active bandwidthpart is associated with a single mapping ratio.
 15. The UE of claim 12,wherein the mapping period is based at least in part on asynchronization signal block to random access channel occasionassociation pattern period.
 16. A method of wireless communicationperformed by a user equipment (UE), comprising: receiving, from anetwork entity, information identifying a quantity of demodulationreference signal (DMRS) sequences supported per antenna panel of thenetwork entity; and transmitting a DMRS communication, with one or moreDMRS sequences configured based at least in part on the quantity of DMRSsequences supported per antenna panel and scrambled using a DMRSscrambling identifier.
 17. The method of claim 16, wherein the DMRSscrambling identifier is based at least in part on a physical randomaccess channel preamble.
 18. The method of claim 17, further comprising:utilizing a scrambling sequence based at least in part on a physicalrandom access channel preamble to scramble bits of a payload and cyclicredundancy check.
 19. The method of claim 16, further comprising:generating a waveform for the DMRS communication, wherein the waveformfor the DMRS communication is a cyclic-prefix orthogonal frequencydivision multiplexing (CP-OFDM) waveform or a discrete Fourier transformspread orthogonal frequency division multiplexing (DFT-s-OFDM) waveform.20. The method of claim 16, wherein a DMRS pattern of the one or moreDMRS sequences is a Type-I DMRS pattern or a Type-II DMRS pattern.